In recent years there has been substantial interest in the 14-aminodihydromorphinone derivatives methoclocinnamox (MC-CAM) and clocinnamox (C-CAM). In order to investigate the importance of the cinnamoyl ring substituent a series of analogues have been prepared with chloro, methyl and nitro-substituents in the 2'-and 4'-positions. Despite some discrepancies between the in vitro and in vivo data, a clear SAR could be observed where the 2'-chloro and 2'-methyl ligands consistently displayed higher efficacy than their 4'-substituted analogues. The new series also followed the well established SAR that 17-methyl ligands have greater efficacy at the mu opioid receptor than their 17-cyclopropylmethyl counterparts.

N-Acetyltyramine was synthesized and electropolymerized together with a negatively charged sulfobutylether-β-cyclodextrin on a boron-doped diamond (BDD) electrode followed by the electropolymerization of pyrrole to form a stable and permselective film for selective dopamine detection. The selectivity and sensitivity of the formed layer-by-layer film was governed by the sequence of deposition and the applied potential. Raman results showed a decrease in the peak intensity at 1329 cm−1 (sp3), the main feature of BDD, upon each electrodeposition step. Such a decrease was correlated well with the change of the charge-transfer resistance derived from impedance data, i.e., reflecting the formation of the layer-by-layer film. The polycrystalline BDD surface became more even with lower surface roughness as revealed by scanning electron and atomic force microscopy. The modified BDD electrode exhibited rapid response to dopamine within 1.5−2 s and a low detection limit of 4−5 nM with excellent reproducibility. Electroactive interferences caused by 4-dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid, ascorbic acid, and uric acid were completely eliminated, whereas the signal response of epinephrine and norepinephrine was significantly suppressed by the permselective film.